Recently, there have been developed stacked semiconductor memory apparatuses with high capacity that comprise a stack of a plurality of semiconductor memories but can be externally controlled in the same way as a single semiconductor memory. For example, a solid state drive (SSD), which includes a nonvolatile memory instead of a magnetic hard disk, comprises a stack of a plurality of flash memory chips of the same type and has an increased storage capacity.
A package containing a stack of 64 1 GB NAND flash memories and a control chip can be externally accessed in the same way as a single 64 GB NAND flash memory. Similarly, 32 DRAM chips can be stacked to form a DRAM having 32 times as much storage capacity as a single chip. Eight microprocessor chips can be stacked to increase the number of multi-core processors eightfold.
The inventors have proposed a technique of wirelessly interconnecting the devices in the stacked semiconductor apparatus described above, which involves inductively coupling coils of wire on semiconductor chips or electronic circuit boards to establish communication (see Patent Documents 1 to 7 and Non Patent Literatures 1 to 8). Patent Document 7 describes a technique of stacking a plurality of semiconductor chips of the same type, connecting the semiconductor chips to a power supply by conventional wire bonding, and inductively coupling the semiconductor chips to establish data communication therebetween.